Baseline Assessment of Skin Resident Memory T Cells in Healthy Unvaccinated Participants
2026年8月11日 更新者：Institute of Tropical Medicine, Belgium
Baseline Assessment of Skin Resident Memory T Cells in Healthy Unvaccinated Participants (GeKoSkimm-Unvaccinated): add-on Study to the GeKoSkimm Trial (= A Randomized Controlled Trial to Compare the Immunogenicity and Skin Imprinting of Intradermal, Subcutaneous and Intramuscular Yellow Fever Vaccination)
In The main GeKoSkimm trial (= A randomized controlled trial to compare the immunogenicity and skin imprinting of intradermal, subcutaneous and intramuscular yellow fever vaccination) the investigators try to understand whether the route of injection (in the muscle, under the skin, or in the skin) when giving the yellow fever vaccine affects the strength of the body's immune response to yellow fever.
More in particular the investigators want to know how well the immune responses are retained in the skin, as this is the place where the virus enters the body after a mosquito bite.
This will be important for vaccines against infections transmitted via bites of mosquitoes and ticks, such as yellow fever virus.
Because this is the first attempt on human samples and only skin samples after vaccination with yellow fever vaccine are available, the investigators want to assess the baseline or background immune response in 'unvaccinated' skin.
Therefore, 40 volunteers will be recruited that have not been previously vaccinated against yellow fever and will not receive a yellow fever vaccine during this study.
The participant will be requested to provide two skin samples from the upper arm and a blood sample to confirm their vaccination status regarded to yellow fever.
調査の概要
詳細な説明
Since baseline punch biopsies were not preferred nor incorporated in the GeKoSkimm trial (= A randomized controlled trial to compare the immunogenicity and skin imprinting of intradermal, subcutaneous and intramuscular yellow fever vaccination) due to ethical and logistical reasons, studying tissue-resident memory T (TRM) cells in a group of healthy unvaccinated participants is necessary to assess natural baseline levels of TRM cells in the skin before vaccination.
The presence TRM cells in healthy and unvaccinated individuals provides a fundamental understanding of normal immune function and biological variability.
This baseline data is essential for interpreting responses to vaccination in the GeKoSkimm trial and detecting any deviations or abnormalities that may arise and assess the baseline or background immune response in 'unvaccinated' skin.
Therefore, 40 volunteers will be recruited that have not been previously vaccinated against yellow fever and will not receive a yellow fever vaccine during this study.
The study consists of two study visits with 14 days (+/- 10 days) between each visit.
Blood sampling of 15 mL is performed on the first visit (1X 10 mL Li-Hep + 5 mL SST) to confirm the vaccination status against yellow fever virus (YFV).
Participants who turn out positive on the YFV virus neutralization test will be retrospectively excluded from analyses, and replaced with new participants.
Skin biopsy sampling (2X 4 mm punch biopsy) in the upper arm is performed only on the second visit, with additional microsampling (microbiopsy and wound blood sampling).
The microbiopsy will be taken from 20 participants, followed by two skin punch biopsies from the upper arm from all participants.
Subsequently, a blood swab will be collected from the wound blood from all participants.
研究の種類
介入
入学 (推定)
40
段階
- 適用できない
連絡先と場所
このセクションには、調査を実施する担当者の連絡先の詳細と、この調査が実施されている場所に関する情報が記載されています。
研究連絡先
- 名前：Prof. Dr. Patrick Soentjens
- 電話番号：+3232476641
- メール：psoentjens@itg.be
研究連絡先のバックアップ
- 名前：Wim Adriaensen
- メール：wadriaensen@itg.be
研究場所
-
-
-
Antwerp、ベルギー
- 募集
- Clinical Trial Site of the Institute of Tropical Medicine
-
コンタクト：
- Yven Van Herrewege
- 電話番号：+3232476557
- メール：yvanherrewege@itg.be
-
コンタクト：
- Jorge Reis Guerreiro
- メール：jreis@itg.be
-
-
参加基準
研究者は、適格基準と呼ばれる特定の説明に適合する人を探します。これらの基準のいくつかの例は、人の一般的な健康状態または以前の治療です。
適格基準
就学可能な年齢
- 大人
健康ボランティアの受け入れ
はい
説明
Inclusion Criteria:
- BMI >/=18,5 kg/m2 and ≤35 kg/m2
- Agreement to share and discuss participant's medical history and medical records when relevant with the study team
- Able and willing to provide written informed consent
- Agreement to refrain from blood donation and other vaccinations during the study
Exclusion Criteria:
- Participants with a confirmed flavivirus infection in the past
- Participants who received a flavivirus vaccination prior to enrolment (e.g. YFV, Japanese encephalitis virus, tick-borne encephalitis virus, Dengue)
- Receipt of any vaccine (licensed or experimental) within 30 days prior to enrolment or during the study
- Active participation in another interventional clinical study with active substance intake or large medical procedures affecting the study procedures during or 1 month prior to enrolment
- Participant has a clinically significant acute illness (this does not include minor illnesses such as diarrhea or mild upper respiratory tract infection) or temperature ≥38.0ºC within 24 hours prior to the visit; inclusion at a later date is permitted at the discretion of the investigator
- Any confirmed or suspected immunosuppressive or immunodeficient state (incl. cancer and human immunodeficiency virus/hepatitis B virus infection); asplenia; recurrent severe infections and use of immunosuppressant medication (including antineoplastic and immunomodulating agents or radiotherapy) within the last 6 months prior to enrolment, except topical or short-term oral steroids (<2 weeks of daily receipt of 20 mg of prednisone or equivalent). Refer to annex 1 for a list of immunosuppressive medication
- Severe and/or uncontrolled cardiovascular disease, respiratory disease, gastrointestinal disease, liver disease, renal disease, endocrine disorder, psychiatric and neurological illness (mild/moderate well controlled comorbidities are allowed)
- History of bleeding disorder (e.g. factor deficiency, coagulopathy or platelet disorder), or prior history of significant bleeding or bruising following venipuncture
- Any significant disease, disorder or planned surgery which may affect the ability of the volunteer to participate in the study or impact (skin) immunity homeostasis
- Suspected or known alcohol or drug dependency
- Known pregnancy
- Tendency to keloid (scar) formation in response to skin damage
- Skin diseases or tattoo at the biopsy site
- In the opinion of the investigator, unlikely compliance to the requirements of the study
- History of thymus dysfunction (including myasthenia gravis, thymoma) or thymectomy
- Individuals who are working at the investigational site or within the research team of this study
- Participants who received immunoglobulins and/or any blood or blood derived products within 3 months preceding the study
- Participants who are currently on anticoagulant therapy
- Participants who are continuously using systemic antivirals
研究計画
このセクションでは、研究がどのように設計され、研究が何を測定しているかなど、研究計画の詳細を提供します。
研究はどのように設計されていますか？
デザインの詳細
- 主な目的：他の
- 割り当て：なし
- 介入モデル：単一グループの割り当て
- マスキング：なし（オープンラベル）
武器と介入
参加者グループ / アーム |
介入・治療 |
|---|---|
|
他の：Healthy unvaccinated participants against yellow fever virus
Healthy participants that have not been vaccinated against yellow fever virus
|
2 x 4mm skin punch biopsies in the upper arm will be taken from each participant at visit 2 with additional microsampling (microbiopsy and wound blood sampling)
Blood sampling of 15 mL (10mL Lithium-Heparine + 5 mL SST) is performed on Visit 1 to confirm their vaccination status regarded to yellow fever
|
この研究は何を測定していますか？
主要な結果の測定
結果測定 |
メジャーの説明 |
時間枠 |
|---|---|---|
|
Estimate the baseline number and proportion of skin-resident memory T cells against YFV (YFV-TRM) in the skin of unvaccinated and healthy volunteers against YFV
時間枠：Day 14 (Visit 2)
|
The number and proportion of YFV-specific T cells within the skin-resident lymphocyte parent population at visit 2, measured by flow cytometry.
|
Day 14 (Visit 2)
|
二次結果の測定
結果測定 |
メジャーの説明 |
時間枠 |
|---|---|---|
|
Estimate the baseline number and proportion of circulating effector- (YFV-TEM) and central-memory T cells against YFV (YFV-TCM) in the blood of unvaccinated and healthy volunteers against YFV
時間枠：Day 0 (Visit 1)
|
The number and proportion of circulating YFV-specific TCM and TEM cells within the CD3+ lymphocyte parent population at visit 1
|
Day 0 (Visit 1)
|
その他の成果指標
結果測定 |
メジャーの説明 |
時間枠 |
|---|---|---|
|
Describe the spatially-resolved position of TRM cells in the skin of unvaccinated and healthy volunteers against YFV
時間枠：D14 (Visit 2)
|
Spatially-resolved YFV-specific TCR clonotypes in the skin at visit 2
|
D14 (Visit 2)
|
|
Determine the baseline TCR diversity index in the skin of unvaccinated healthy volunteers against YFV
時間枠：Day 14 (Visit 2)
|
TCR diversity index in the skin at visit 2
|
Day 14 (Visit 2)
|
|
Estimate the baseline cytokine and chemokine concentrations in capillary blood, and microbiopsies of unvaccinated and healthy volunteers against YFV
時間枠：Day 14 (Visit 2)
|
The number of cytokine and chemokine concentrations (ng/ul) in capillary blood, and microbiopsies at visit 2
|
Day 14 (Visit 2)
|
|
Estimate the baseline YFV-specific IgG/IgM levels in capillary blood of unvaccinated and healthy volunteers
時間枠：Day 14 (Visit 2)
|
IgG/IgM levels (mean fluorescence intensity) in capillary blood at visit 2
|
Day 14 (Visit 2)
|
協力者と研究者
ここでは、この調査に関係する人々や組織を見つけることができます。
研究記録日
これらの日付は、ClinicalTrials.gov への研究記録と要約結果の提出の進捗状況を追跡します。研究記録と報告された結果は、国立医学図書館 (NLM) によって審査され、公開 Web サイトに掲載される前に、特定の品質管理基準を満たしていることが確認されます。
主要日程の研究
研究開始 (実際)
2026年8月10日
一次修了 (推定)
2026年11月15日
研究の完了 (推定)
2026年11月15日
試験登録日
最初に提出
2026年5月18日
QC基準を満たした最初の提出物
2026年6月8日
最初の投稿 (実際)
2026年6月9日
学習記録の更新
投稿された最後の更新 (実際)
2026年8月13日
QC基準を満たした最後の更新が送信されました
2026年8月11日
最終確認日
2026年8月1日
詳しくは
本研究に関する用語
追加の関連 MeSH 用語
その他の研究ID番号
- 1966/25
医薬品およびデバイス情報、研究文書
米国FDA規制医薬品の研究
いいえ
米国FDA規制機器製品の研究
いいえ
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